No longer receive email alert when I have a new direct message

[AFAustin]

Under My Account > Preferences, I have checked "Receive email when a new direct message is received". And I've always received these email alerts.

I haven't changed this setting, but recently I no longer get the emails telling me of a new direct message (and I have checked my spam folder).

Any idea why this is and what I can do to fix it?

Thanks,

Andrew